The Godsfall Chronicles Book 7, Chapter 56 - Core Space

Belial tugged his invisible threads controlling the Eternal. They lurched toward Cloudhawk, attacking the intruders with lethal intent.
Four at once went after the Demon King's successor. Their arms reformed into solid black pikes which they flung toward their quarry. On the surface they didn't seem to be formed of energy but of darkness, like all the shadow of the world gathered together.
Their strikes were strong enough to drill through mountains.
Cloudhawk's cloak shifted in a non-existent breeze as power coursed through him. A wave of pale white power emerged, shoving everything away on all sides. Those dark spikes ground to a halt, hung in the air for two seconds and then began to dissolve inch by inch. What remained were clouds of black particles.
Four of them had been caught in the blast, but instead of dissolving like their initial blows, they released beams of light protecting them from Cloudhawk's ire.
Next his arms reached out. From within Cloudhawk's sleeves came two, four, eight, ten streams of silver light. Silver Serpents, dashing across the room like greased lightning. If time froze in that moment the liquid steel of them would be revealed, and they would portend death.
Woosh, woosh, woosh!
The Silver Serpents instantly shot through the puppets, at least for or fight each. The number Cloudhawk released kept increasing.
If the aim of Cloudhawk's attack were just this, it would be ineffectual. But rather than just a ripping attack, the Silver Serpents were vessels to inject the puppets with Castigation Fire. Everything they touched were infected with hungry green light.
The fires spread quickly. In a matter of seconds the puppets were writhing masses of cracked skin, their insides turned to ash. Spurts of Castigation Fire belched from fissures in their skin, from their eyes and mouths, until they were naught but columns of flame.
Cloudhawk's hellish fires did not extinguish. Through his powers he ensured the victims continued to burn, heedless of their immortal bodies. Until his mental fortitude ran dry, these puppets would not be fit to keep fighting.
Belial looked on with a wooden expression. "Castigation Fire..."
The relic of a Demon Elder! In fact, the former owner of that power had a history with Belial.
Both were artisans and Elders. However, Belial's former colleague fell during the Great War. It was then his Castigation Fire fell into the hands of humans. Now, after so long, his old friend's relic was before him again. He could not help but feel the pang of yearning for those old days.
Belial steeled his resolve. That old friend was as stupid as all the others. Blindly he followed the fallen Demon King, a choice which got him killed. He would not follow in the fool's footsteps - just another meaningless sacrifice in someone else's war.
Castigation Fire was troublesome. However, if you knew its secrets the response was clear!
Belial breathed forth a torrent of pitch-black fire. It formed into smoldering orbs which crashed into the bodies of the burning puppets. Two fires of opposing origins combated, weaving through the Eternal until eventually it appeared Belial's power won. Castigation Fire withered and died within his guardians.
Moments later, the puppets were restored. Surging power sent them back into the fray as strong as ever. Their bottom halves were vortexes of energy, and their upper halves were a flurry of dark weapons. Abaddon, Frost and Autumn put up a desperate resistance, each only able to hand two at a time.
To add to their intractability, the puppets fought under Belial's guidance. They moved in and retreated together as a cohesive unit. Immortal bodies made them fearless in the face of attacks, and empowerment from the demon Elder made them all the more brazen. The four intruders were quickly locked down.
Frost swung his spear around, whipping it through the puppets. His enemies took the strike, allowing the spear to run them through. Their dark powers held the weapon - and Frost - in place. They raised their black weapons to cut him down.
He was in danger of being beheaded, then - woosh! He thrust his left hand and the spear released a thin gash of light. It fended off the deadly blow, giving him enough time to wrench his spear free. But as he was getting his footing, two more puppets moved in.
With a sword in his left hand and the spear in his right, he fought off their attacks. What he could not find was a way to fight back. Under their assault his guard was slipping. The same scene was repeating near Abaddon. They were being overwhelmed, especially since Belial could coordinate his puppets against them.
The shrill tone of a flute filled the air. The Eternal froze as though caught in a mire.
In the same instant vines appeared from the ether and formed a temporary barrier. For the moment, they had time to catch their breath.
This conflict far exceeded Autumn's skill, so she allowed the Shepherd God to take control and flood her with power. But the Shepherd God's skills were in summoning, which sadly were not very useful here. Belial was a strong opponent, and his many relics gave him tremendous advantage.
Once again, Belial sought to turn the tide. Another burst of dark fire exploded from him like a flood. As they washed over the Shepherd God's vines, her summoned foliage was instantly reduced to ash. That inky darkness hung in the air for a moment then formed into a roaring dragon.
This was not normal fire.
Cloudhawk could sense that this power was impossible to defeat directly, even by the likes of Castigation Fire. The only explanation was that it was a relic meant to protect against his green fires. Belial's black counterpart had incredible destructive power and limitless energy. Cloudhawk feared before long the entire place would be swallowed up by it.
"Handle these things!" Cloudhawk shouted at the others.
Before his allies could react, he threw himself at Belial. Charging straight through the evil flames, he grabbed the demon Elder by his arms and summoned his spatial powers.
It was a dangerous and foolish act, one Belial hadn't been prepared for.
Cloudhawk's teleportation skills were now almost instantaneous. Unless one avoided his touch, it was hard to interrupt him. By the time Belial realized what was happening, it was already too late. The landscape around him shifted from a cramped tunnel to another place peppered with crystals.
Cloudhawk's strategy was simple; teleport Belial away from where he was strongest. Hopefully it would break his hold over the Eternal puppets, leaving them with only their own powers to rely on. Things would go much smoother for Autumn and the others.
As for this guy, Cloudhawk would deal with him alone.
But to his surprise, Belial was not upset at being forcibly removed from the crystal. Instead, his face lit up. "This is it! It's here!"
What the fuck is he so thrilled about?
Belial had thought he would have to dig for many more days before reaching the center, but Cloudhawk had brought him directly to the core of the Source. In trying to defeat him, the Demon King's successor had delivered him to what he wished!
Here they stood, at the heart of what the gods left behind. All the crystals around it formed later. Whatever the gods had left behind, buried under the earth, surely had to be right here.